Printing ink



UNITED STATES PATENT or-ncs.

WALTER w. EVANS AID BENTON DALI-S, OI AKRON, OHIO, ASSIGNOBS TO THE B. I.

GOODRICH COIPLNY, O1 NEW YORK, N. Y., A CORPORATION 01' NEW YORK.

rmn'rme nix.

110 Drawing.

To all whom it may camera:

Be it known that we, WALTER W. EVANS and BENTON DALES, citizens of the United States, residin at Akron, in the county of Summit and tate of Ohio, have invented a certain'new and useful Printing Ink, of which the following is a specification.

This invention relates to sticky coloring material such as are applied to print-sheets by printing forms, and more particularly to substantially non-fluid printin inks used in inting newspapers and the li e, and it has for its principal objects to provide a coloring material which may be applied to a printing form with the usual printing apparatus comprising an inkinglate and one or more ink-distributing ro lers without gummin up the printing apparatus over an extende period of continuous use, and an ink which will not injure rubber-composition ink-distributing rollers.

Water-solutions of film-forming materials typical examples of which are glue, gum arabic, cherry dextrine and starch, and thick syrup wifi l i dld solid pigment-particles in suspension, but when thickened to a paste and spread thinly on the inking plate, inkdistributing rollers, or type of a press they dry so rapidly that they are im ractical for use on a printing apparatus. 'e, however, employ a mixture of one or more of these water-solutions and a viscous watersoluble slow drying liquid and more particularly a polyhydric alcohol of the saturated series, such as glycerine, the mixture having a consistency of a slow-flowing or substantially non-fluid paste, and control the drying properties by varyin the roportions used so that the paste wifi not ry rapidly on a printing apparatus but will dry rapidly on an absorbent print-sheet such as paper.

Film forming materials give a desirable gloss to the print, hold part of the pigment in a film on the surface of the print sheet, and act in the nature of a binder to prevent a blurring of the print on a wet print-sheet due-to capillary action. This function of the glue or gum is more evident when a part of the glycerine is replaced by a sugarsolution. If a syrup is used in the mixture we also add the film-forming material but whether used with of without syrup the glue or gum is not added in such proportions as to materially thicken the mix or add substantially to its properties as a vehicle for Specification of Letters Patent. Patented J an, 24, 1922, Application filed April 8, 1921. Serial No. 459,882.

suspending solid pigment-particles, it having been found that the presence of a con- S1 erable quantity of the film-forming material causes the mixture to gum on the type necessitating a frequent cleaning of the lat ter to prevent a blurring of the print.

When using glue or related substances we prefer to treat them to prevent their setting or stiffenin in the mix, and we also prefer to obtain t is result without the use of hydrolyzing or ionizing salts which would cause the metal of the inking plate, of the type, to rust. A glue solution may be heated until it will remain indefinitely without setting although when using glue as the film-forming material we do not wholly limit ourselves to this means of treating it to keep it from stiffening.

By way of example, we heat a 20 per cent solution of glue'in water under 75 pounds steam-pressure in a closed vessel for twenty to thirty minutes. We may then take by weight 20 parts of a 20 per cent solution of glue, parts offglycerine and 16 parts of carbon-black. The glue and glycerine are first mixed together forming a thick viscous liquid, and the carbon-black is then stirred in, acting as a drying or thickening agent to form the mixture into a thick .paste which may be molded to some extent, and only slowly loses any given shape. The proportion of glue used 1s about 4 parts by wei ht of dr glue to 75 parts of glycerine. t find th parts of dry glue with 7 5 parts of glycerine or with 75 parts of glycerine and syrup, but

e v at we can use up to approximatelydO of about the viscosity of glycerine, up to approximately 6( r cent of the glycerine content, and the pigment may be dissolved or suspended in 'a colloidal state. An ink base or pi e'nt vehicle comprising a mixture of g ycerine and a syrup containing dextrine may be used without adding glue and if the syrup contains also dextrose the drying and. sticky characteristics of the ink are much improved especially when the ink is used on rapidl operating multiple presses such as are emp oyed for newspaper printing. When a water-soluble pigment is used the viscous liquid may be thickened to pasteform by a finely divided solid filler such as clag, as the drying or thickening a ent.

wing to the fact that neither t ewater solutions nor the polyhydric alcohols will attack rubber, the ink may be used on presses having rubber-covered ink-distributing rollers without causing the rubber-composition to swell or deteriorate as is the case when oil base inks are used, thus overcomin one of the principal objections to the use 0 rubber-rollers. The ink will make a permanent print on paperor the like, which print cannot be removed or blurred appreciably by merely wetting the print sheet, but the ink may be easily removed from a non-absorbent printing apparatus by washing the inkcoated parts thereof with water.

It is well known that glycerine or glue may be used with a syrup solution as a pigment-vehicle in copying, writing, or other fluid'inks, but so far as we are aware we are the first to produce a water-soluble printing ink-paste comprising a film-forming material which does not constitute the body of the ink, but which modifies the properties of the pigment vehicle, gives a gloss to the print and leaves on the pa er a print formed in part by a thin film on tlie surface thereof.

We claim:

1. In a rinting' ink, a mixture of a viscous liquid comprising by weight at least 40% of a polyhydric alcohol of the saturated series, and a relatively small amount of a solution of a film-forming material, together with a solid drying agent.

2. A printing ink comprising a mixture of glycerine, water-solution of a film-formmg material, present in an amount not exceeding 20% of the amount of the said glycerine, and a solid pigment.

3. In a printing ink, a pigment-vehicle comprising glycerine and a syrup having a viscosity substantially the same as that of glycerine, a non-setting water solution of glue, and a pigment, the proportion by weight of dry glue to the glycerine and syrup being not greater than 10 to 75.

4. In a printing ink, a mixture comprising glycerine, a smaller amount by weight of a non-setting solution of glue, and a solid pigment, said mixture having the consistency of a substantially IIOIlcflllld paste.

5. In a printing ink, a mixture comprising glycerine, a smaller amount by weight of a non-setting solution of glue, said solution being free from ionizing, salts, and carbon-black in proportion to said liquids to form therewith a substantially non-fluid paste.

6. A printin ink comprising by weight 10 parts of a glue solution not exceeding a strength of 20%, 60 parts of amixture of glycerine and a syru having a viscosity of about that of glycerme, the said glycerine constituting at least 40% of the mixture, and carbon-black present in such proportion to said liquids as to formtherewith a substantially non-fluid paste.

In witness whereof we have hereunto set our hands this 7th da ofApril, 1921.

" WA TER W. EVANS.

' BENTON DALES. 

